esp8266

reset causes

reset causes:
    0: 
    1: normal boot
    2: reset pin
    3: software reset
    4: watchdog reset

boot device:
    0:
    1: ram
    3: flash

get flash_id using esptool.py

esptool.py --port "$COMPORT" --baud 460800 flash_id

    Manufacturer: e0
    Device: 4016
    Detected flash size: 4MB

known chip ids

  4 Mega Bits / 512K Byte      = ID 4013h
  8 Mega Bits /  1 Mega Byte   = ID 4014h / 6014h
 16 Mega Bits /  2 Mega Bytes  = ID 4015h
 32 Mega Bits /  4 Mega Bytes  = ID 4016h
 64 Mega bits /  8 Mega Bytes  = ID 4017h
128 Mega bits / 16 Mega Bytes  = ID 4018h

get chip_id using esptool.py

esptool.py --port "$COMPORT" --baud 460800 chip_id

    Chip ID: 0x00c1120b        last three octets of mac c1:11:02
                               used for station and ap network interface

pins to use for hardware SPI

SPI CLK = GPIO14
SPI MOSI = GPIO13
SPI MISO = GPIO12